Day care, school and other activities offer children stimulation, education as well as important social time. However, gathering in groups is particularly challenging for young children as they are more prone to infections, due to their immature immune system.

During an average year, a child gets sick 6 to 12 times with colds or influenza, which commonly cause runny nose, fever and coughing. The infections usually resolve in 7 to 10 days but lead to absences from day care for the child and work for the parents.

What is the immune system?

The immune system is the body’s way of protecting itself from pathogens, like bacteria, viruses, fungi and parasites. Multiple tissues and cells throughout the body work together to orchestrate an effective response to infections to keep your healthy.

How does the immune system work?

The immune system has two main parts that complement each other: the innate immune system and the adaptive immune system.

The innate immune system

The innate immune system is your first line of defence. It is inherited and active from birth. The innate immune system includes the skin, the mucous membranes that line the mouth, nose and digestive track, the gut microbiota and other general barriers to infections. The innate immune system also helps detect the presence of pathogens, recruits other immune cells to attack and triggers inflammation and fever.

The adaptive immune system

In contrast, the role of the adaptive immune system is to create a targeted defence against specific infections. It is responsible for making antibodies that recognize and neutralise individual pathogens, or tag them for destruction. It also involves memory cells that circulate for months or years after an infection ends so that your body can respond quickly if the pathogen returns.

Childrens immune system

A child’s adaptive immune system develops with age and through exposure to a variety of infections. Lots of new and potentially dangerous microbes and viruses enter the body through the digestive tract, and therefore the gut plays an important role in your child’s immune health. A majority of the body’s immune cells are located in the gut and cells lining the small intestine secrete huge numbers of antibodies. Additionally, the gut microbiota help train the adaptive immune system to distinguish between pathogens, beneficial microbes and the body’s own cells.

The body also can experience passive immunity for a short time when it receives antibodies from an outside source. For example, antitoxin treatments contain antibodies that provide passive immunity.

How the immune system grows up

A baby’s immune system doesn’t become mature until around two or three months of age, making babies especially susceptible to viral and bacterial infections. Fortunately, the foetus receives antibodies from the mother through the placenta, which protect the baby from infections during the first weeks of life. Breastmilk also delivers protective antibodies and can help prevent allergies.

Parents can help protect their baby early on by asking visitors to wash their hands before holding the baby and limiting exposure to people outside the family for the first six months.

After this period, however, a baby needs to be exposed to harmless bacteria in the first three years of life to build up a healthy and diverse gut microbiota. These bacteria help the immune system identify pathogens and provide a barrier against infections.

Keeping kids’ immune systems strong

While occasional colds and flus are inevitable, there are several ways to strengthen a child’s immune system.

Eating a varied diet that is low in fat but rich in fruits, vegetables and whole grains will keep the body and immune system healthy. A high-fibre diet will also feed the gut microbiota. Additionally, getting adequate amounts of vitamins and minerals ensures that the immune system can produce the cells, antibodies and other molecules needed to fight disease.

Sleep recommendations*

Children also should get plenty of sleep to keep their immune system in optimal shape. Lack of sleep interferes with the production of immune signalling molecules called cytokines that help fight infections.

  • Infants 0 to 3 months old, 14 to 17 hours per day
  • Infants 4 to 11 months old, 12 to 16 hours per day
  • Toddlers 1 to 2 years, 11 to 14 hours per day
  • Children 3 to 5 years, 10 to 13 hours per day
  • Children 6 to 12 years, 9 to 12 hours per day**
  • Teenagers 13 to 18 years, 8 to 10 hours per day**

* The World Health Organization
**The American Academy of Sleep Medicine

Strengthen the immune system from the inside

Most of the immune system is located in the gut and by taking care of your child’s digestive system you can help him or her to stay healthy and strong. A healthy microbiota reduces the risk of infections and offers an overall better quality of life.

Vitamin D – a natural way to stay healthy

Vitamin D is needed for normal growth and bone development in children and also is essential for a strong and well-functioning immune system. It is important at every stage of life, but especially for rapidly growing infants and children.

Minimize the spread of infections

There are more ways to help reducing the spread of infections, keeping your family healthy and minimizing sick days.

  • Make sure both you and your child wash your hands frequently with soap and water, especially when coming home from day care or work and public transportation.
  • Avoid sharing the same towel.
  • Avoid crowds during the cold and flu season.
  • Teach your child to sneeze or cough in a tissue or the crook of the elbow, instead of the hand.
  • Let your child stay at home if he or she is sick.